Method and Apparatus for Monitoring a Material Medium

ABSTRACT

A material medium, such as an optical fiber or electrical cable, is used to carry services. The material medium is monitored with at least one diagnostic sensor. The diagnostic sensor may measure the operational health of the material medium, or may measure local environmental conditions around the material medium.

BACKGROUND OF THE INVENTION

The present invention relates generally to a material transmissionmedium, and more particularly to method of monitoring the transmissionmedium.

There are multiple industries which rely upon long stretches of amaterial medium in order to deliver a service to dispersed customers.Examples of such industries include (1) telecommunications and (2)electrical power. Effective delivery of these services requires that theintegrity of the material medium be maintained.

Unfortunately, it is common for a portion of the material medium toexperience an environmental condition or acute stress that causes thematerial medium to become inoperable or physically compromised.Currently, significant labor, time and money are spent in trying todetermine the location and cause of a material medium's compromise.

Even when a location of a problem in the material medium is identified,the reason for the problem is often not determined. The inability todetermine a cause of the problem may be due, at least in part, to theextended time needed to determine the cause. By the time the fault islocated, the cause of the problem may have already dissipated orrelocated. For example, if the fault was caused by flooding, the watermay have receded, leaving no sign of flooding that led to the fault.Alternatively, if the problem was caused by a physical blow to thematerial medium, the cause of the blow is likely to be far removed bythe time the location of the fault is detected. There are several otherpotentially damaging forces which are similarly transient and leavelittle trace once the damage has been done.

Therefore, it would be advantageous for suppliers of services overmaterial transmission media to have a method for more quickly andaccurately determining the location and/or the cause of a problem in thetransmission medium.

Even more advantageously, suppliers of the service would benefit frombeing able to preempt a problem by assessing that there is a threat to amaterial transmission medium before there is a loss of service. If theywere able to make such an assessment, the suppliers could attempt toremove or manage potential problems before their service is interrupted.

However relevant industries face significant limitations on what theycan do to monitor their material media. Often, the material mediumnetwork is already installed. Therefore, a monitoring system would haveto be readily adaptable to the already existing infrastructure.Additionally, “bandwidth”—the transmission capability of the materialmedium—may be near maximum. This means that a monitoring system would beprohibitive if it required utilizing significant bandwidth in thematerial medium as part of the monitoring or reporting process.

While there may be methods that are currently used for determining thelocation of faults; these methods tend to be slow, labor intensive, andinaccurate. Therefore, there is a need to develop a quicker, less laborintensive, and more accurate method of fault detection. Additionally, itwould be advantageous if this monitoring system could also predictproblematic areas in order to facilitate preventative maintenance.

There is therefore a need for an improved system and method ofmonitoring a material medium.

The current invention is based, at least in part, on a recognition ofthe following limitations which may be encountered when monitoring amaterial medium for a fault or a potential fault: (1) the amount of timeand labor needed to find a fault, (2) the need for change in a currentmaterial medium infrastructure to support a monitoring effort, or (3)the reduction in available bandwidth in a material medium due to amonitoring device using the material medium to send data.

BRIEF SUMMARY OF THE INVENTION

These limitations are avoided, in accordance with one embodiment of thecurrent invention, by monitoring a material medium with at least onediagnostic sensor, and using an electromagnetic wave (EM) signal, suchas a radio frequency (RF) signal, to wirelessly transmit the sensordata. The diagnostic sensor may measure the operational health of thematerial medium or of the local environment around the material medium.Using an EM signal to transmit sensor data allows for a fast, lowlabor-intensive monitoring approach. Additionally, it avoids the need toeither; (1) transfer the data by intruding into the monitored materialmedium, or (2) set up an independent material medium system to transferthe data.

In accordance with another embodiment of the invention, the diagnosticsensor and/or the means for transmitting an EM signal—may be powered byinduction from the EM energy flowing within the material medium orwithin a conduit which houses the material medium. Examples of amaterial medium include an optical fiber or an electrical cable.Utilizing induction as the primary power source avoids the need to powerthe sensor and transmitter by: (1) intruding into the material mediumbeing monitored, (2) setting up an independent network of materialmedium, or (3) using an exhaustible power supply such as anon-rechargeable battery. In one example, an energy harvesting module isused to capture the energy induced, using any scientific phenomenon, byan EM energy flow in the material medium. In a further example, theenergy harvesting module includes a capacitor-like slow-chargingelectrical storing device to store energy.

In accordance with another embodiment of the invention, the diagnosticsensor itself contains RF transmission means for transmitting sensordata. In another embodiment, there is a separate EM transmission devicethat is used to transmit the sensor data.

In accordance with a further embodiment of the invention, the means fortransmitting an RF signal—whether it is part of the diagnostic sensor ora separate device in communication with the diagnostic sensor—is able toself-organize into a store-and-forward multi-hop wireless mesh networkwith another device enabled to transmit an RF signal.

In accordance with another embodiment of the invention, the RF signal istransmitted utilizing a waveguide. Some examples of objects which can beused as waveguides include a material medium and the conduit housing amaterial medium. For the purposes of this invention, transmitting awireless EM signal—such as an RF signal—over a waveguide is considered awireless transmission. A wired transmission is when non-wireless EMsignal is transmitted by a material medium.

In accordance with another embodiment of the invention, the diagnosticsensor measurements are retrieved from the wireless mesh network bycommunicatively linking a roaming unit—the roaming unit capable ofreceiving an RF signal—to a device within the wireless mesh network, thedevice being able to transmit an RF signal to the roaming unit.

In accordance with another embodiment of the invention, diagnosticsensor data is transmitted to a back haul network, wherein—within themesh network—at least one of the devices capable of transmitting RFsignal is in communication with the back haul network. In oneembodiment, the back haul network is the Internet.

In accordance with another embodiment of the invention, the devicecapable of transmitting an RF signal is a device selected from thefollowing list: a Zigbee device, a Wibree device, an EnOcean device, anda SNAP device.

In accordance with another embodiment of the invention, the materialmedium being monitored is placed under the ground.

In accordance with another embodiment of the invention, the materialmedium being monitored is located inside a facility, building, orresidence. In one embodiment, the material medium goes to an end-user'sdevice inside the facility, building, or residence.

In accordance with another embodiment of the invention, the diagnosticsensor is used to measure one of the following: (1) EM energy flow, (2)temperature, (3) pressure, (4) moisture, (5) vibration, (6) percentageof a designated chemical, and (7) wind speed. In one embodiment, thesediagnostic sensor measurements are used to monitor an operational statusof a material medium. In another embodiment, these diagnostic sensormeasurements are used to monitor a structure or natural resource in thevicinity of the material medium. Some examples include monitoring: abridge, a tunnel, a highway, a railroad track, and a body of water.

These and other advantages of the invention will be apparent to those ofordinary skill in the art by reference to the following detaileddescription and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of a prior art system fortroubleshooting a downed telecommunication's material medium.

FIG. 2 is a flowchart representing a process used in an aspect of thecurrent invention.

FIG. 3 is a schematic representation of a system according to thecurrent invention for monitoring and troubleshooting any materialmedium, including powering the monitoring instrumentation.

FIG. 4 is a schematic representation of alternative powering optionsaccording to an aspect of the current invention.

FIG. 5 further illustrates powering options for a material medium,specifically an optical fiber.

FIG. 6 is a schematic representation of an interconnection betweenseparate devices, one for monitoring and the other for transmittingdata.

FIG. 7 is a schematic representation of a data harvesting scenario inwhich data is collected with a roaming unit.

FIG. 8 is a flowchart for a Mesh Network embodiment of the invention.

FIG. 9 is a schematic representation of a mesh network comprisingdiagnostic sensors and RF data transmission devices.

FIG. 10 is a schematic representation of communication with a waveguidein a mesh network.

FIG. 11 is a schematic representation of communication by couplingantennas to a material medium in a mesh network.

FIG. 12 is a schematic representation of an embodiment which combinesdifferent aspects of the invention.

FIG. 13 is a schematic representation of a mesh network deployment wheredata is collected with a roaming unit.

FIG. 14 is a schematic representation of a mesh network deployment wheredata is collected with a back haul communication link.

FIG. 15 is a schematic representation of a mesh network topology as ahierarchy relationship.

FIG. 16 is a schematic representation of monitoring a diagnostic sensorlocated on an above and below ground material medium.

FIG. 17 is a schematic representation of monitoring a material medium asit goes to an end device in a facility, building or residence.

FIG. 18 is a schematic representation of some possible diagnostic sensormeasurements of interest when monitoring a material medium.

FIG. 19 is a schematic representation of how a material medium can beused to monitor environmental conditions in a tunnel.

FIG. 20 is a schematic representation of how a material medium can beused to monitor environmental conditions on a bridge.

DETAILED DESCRIPTION

There are multiple industries which rely upon long stretches of materialmedium in order to deliver a service to disperse customers. Examplesinclude (1) the telecommunications industry and (2) the electrical powerindustry. Effective delivery of these services requires that theintegrity of the material medium be maintained.

However, with so many miles of material medium, it is common for aportion of material medium to experience some environmental condition oracute stress that causes the material medium to become inoperable orphysically compromised. Currently, significant labor, time and money arespent in trying to determine the location and cause of such acompromise.

FIG. 1 shows an exemplary prior art system for troubleshooting a failedtelecommunication's material medium. A customer, noticing a telephoneservice interruption, 101, contacts a telecomm service provider andinforms the service provider of an inoperable telephone line.

In order to locate the trouble spot in the communication's materialmedium, 106, the service provider may use a testing tone generator, 107,to generate test signals, 104, from a particular location. Then, theprovider checks at various demarcation (DMARC) points, 103, along thematerial medium to see if the signal is received. At the customer'slocation, a final DMARC point, 102, is checked before the telephoneservice enters the user's home. When it is determined where the testsignals are no longer detected, the service provider is able to identifya stretch of material medium that is the likely location of the fault.

The next step, however, leads to considerable delay and monetaryexpenditure. The service provider sends out a repair employee or team,105, into the field to search for the faulty stretch of material medium.Since there is often a significant distance between DMARC points,finding the specific location of the fault in the material mediuminvolves significant effort. Distances of the range of [Inventors,please fill in values] are relatively common. Furthermore, for therepair employee or team to investigate the material medium's ability tocarry signal at a particular location, the material medium needs to bephysically accessed. This can be quite difficult if the material mediumis located in a hard to access location, such as below the ground orhigh in the air. Accessing the line needs to be repeated several timesuntil the fault location is finally pinpointed.

In additional to the extended delay causing the customer anguish and theservice provide significant labor expenses, this delay causes anotherproblem. Since it may take significant time to find the specificlocation of the fault, by the time location is determined the reason forthe problem is often not determined. The inability to determine a rootcause of the problem may be due—at least in part—by the extended timeneeded to determine the cause. By the time the fault is located, thecause of the fault may have already dissipated or relocated. Forexample, if the fault was caused by flooding, the water may havereceded, leaving no sign of the flooding that led to the fault.Alternatively, if the fault was caused by a physical blow to thematerial medium, the cause of the blow is likely to be far removed bythe time the location of the fault is detected. There are several otherpotentially damaging forces which are also transient and leave littletrace once there have dissipated.

Many the barriers stand in the way of improving this problem. Forexample, many material medium networks are already established.Therefore, a monitoring system would have to be adaptable to the presentinfrastructure, such as below ground and elevated material media.Additionally, “bandwidth”—the service capacity of a material medium—isoften near maximum capacity. This means that a monitoring system wouldbe prohibitive if it required utilizing significant bandwidth in thematerial medium. Bandwidth may be reduced if the monitoring systemutilizes the material medium to either receive power or transmit data.

Given the current constraints, there is therefore a need for a systemand method of monitoring a material medium which significantly improvesupon current methods of fault detection. Additionally, it would beadvantageous if an improved monitoring system could also predictproblematic areas in order to facilitate preventative maintenance.

Therefore, it would be advantageous to have a system and method for morequickly and accurately assessing a cause of a fault that can both: (1)integrate into existing material media infrastructure, and (2) minimizeuse of material medium bandwidth. Additionally, it is desired to have asystem and method for being able to predict future problems by assessinga potential threat to a material medium before there is a loss ofservice.

The current invention solves the following challenges that areencountered when currently monitoring a material medium for a fault or apotential fault: (1) requiring a time and labor intensive investigationto find a fault, (2) needing a significant change in a current materialmedium infrastructure to support a monitoring effort, or (3) reducingavailable bandwidth in a material medium due to a monitoring deviceintruding into the material medium to send data. These challenges areavoided, in accordance with a feature of the current invention, bymonitoring a material medium with at least one diagnostic sensor, andusing an electromagnetic wave (EM) signal to transmit the sensor data.The diagnostic sensor may measure the operational health of the materialmedium, or the status of the local environment around the materialmedium. Using an EM signal such as a radio frequency (RF) signal towirelessly transmit sensor data allows for a fast, low labor monitoringapproach. Additionally, it avoids a need to either; (1) transfer thedata by intruding into the monitored material medium, or (2) set up anindependent material medium system to transfer the data.

FIG. 2 illustrates the above solution with a flowchart. After theprocess is begun, at step 201, a location on a material medium ismonitored with a diagnostic sensor, at step 202. Data from thediagnostic sensor is then wirelessly transmitted using an EM signal,such as an RF signal, at step 203. The process ends at step 204.

This aspect of the current invention solves the previously mentionedproblems in the background art in at least the following ways. Thediagnostic sensor can be placed anywhere along a material medium, and isnot dependent on gaining physical access to the inside of the materialmedium. In the example of the telecomm industry, this means that adiagnostic sensor does not need to be placed at a DMARC point.Therefore, a utility service provider has significantly more flexibilitythan in the prior art. The status at any point along a material mediumcan be assessed automatically by the diagnostic sensor and transmittedby EM signal. This gives insight into the material medium's operationwithout needing to physically access the material medium. Additionally,wireless transmission of the diagnostic sensor data with an EM signal,such as an RF signal, avoids a need to (1) transfer the data byintruding into the process being monitored, or (2) setting up anindependent material medium system to transfer the data. Since there isno limit on how many sensor setups are placed along a material medium,the service provider can get as much real time sensitivity as they wantby simply placing more sensor setups along the material medium.

FIG. 3 is a schematic representation of a system according to thecurrent invention for monitoring and troubleshooting any materialmedium, including powering the monitoring instrumentation. A sensorsystem comprises a diagnostic sensor, 304, and an EM communicationmeans, 305. In one example, an RF signal is the EM signal used. Thesensor setup receives its power from a power source, 306. The sensorsetup as a whole is shown as 302. It is located in the vicinity of amaterial medium, 303. The EM communication range is represented by 301,which shows how far the EM signal may be transmitted by the EMcommunication means. Some examples of the capabilities of a diagnosticsensor are measuring the presence and quality of electromagnetic (EM)flow along a material medium, and measuring the local environmentalconditions in proximity to the material medium—for example temperature,moisture, and pressure. Diagnostic sensor functions are discussedfurther in FIG. 18.

In one embodiment, the EM communication means, 305, may be a part of thediagnostic sensor. In another embodiment, 305 may be a separate deviceconnected to the diagnostic sensor. In yet a further embodiment, 305 maybe a separate device in communication with the diagnostic sensor, butnot otherwise physically connected to it.

There are several options available for powering the sensor setup. Themost straight forward method is using a power line. The advantage ofthis option is that it provides a continuous supply of electrical power,which enables a device to perform more complex computations. Thedisadvantage of this option is the limited availability of such acontinuous supply of electrical power. In order for a sensor setup toaccess a power line, this setup must be: (1) installed at a demarcation(DMARC) point which is a location where the material medium can be moreeasily accessed, (2) placed at a point where the material medium hasbeen accessed, or (3) powered by a separate power line.

Each of these options for providing power has a disadvantage. If poweris obtained by placing the sensor only at DMARCs, then only a few suchpoints exist along long stretches of material medium. Thus, only a fewsensor setups would be able to be located next to the material medium.Additionally, sending power over the material medium being monitoreddecreases the available bandwidth. This runs counter to a primary goalof the current invention, which is to maintain as much bandwidth aspossible for use in transmitting the utility's EM energy. A disadvantageto providing special access points in the material medium for the sensorsetups is that this requires significant labor and therefore cost toinstall, especially if multiple sensor setups will be used to monitorthe material medium. A disadvantage to running a separate power line isthat this line itself requires its own periodic maintenance and acutetroubleshooting if the power line goes down. This adds significant costand labor to maintaining the material medium, which runs counter to aprimary goal of the current invention. Additionally, significant laborand material cost will be accrued with such an installation, especiallysince a material medium is often installed in hard to reachlocations—such as below ground or elevated from ground level.

Due to the disadvantages of providing power line access, such a poweringscheme may be reserved for use with special sensor setups that need thecontinuous power supply to run more resource consuming tasks. In oneembodiment, these special sensor setups are located at DMARC points,which is usually the most straightforward of the three power line accessoptions previously mentioned to implement.

Another option for powering a sensor setup is to use regular batteries.Some of the advantages of regular batteries are that they providecontinuous power and they are relatively inexpensive to implement.However, a significant disadvantage to using regular batteries is thatthey are exhaustible—they eventually lose their charge. When a batteryloses its charge, it must either be replaced or recharged off-line, whena recharging is an option.

Due to the disadvantage of being exhaustible, the most practical use fora regular battery is as an easy backup power supply. However, in oneembodiment, a regular battery is used as a primary power source when noother powering option is feasible.

A further option for powering the sensor setup—which, in one embodiment,is the most preferred option—is using energy induced by anelectromagnetic (EM) energy flow of a utility through the materialmedium or through a conduit which houses a material medium. TransportingEM energy through a conduit which houses the material medium allowsusing this powering method even when the energy flow on the materialmedium is not sufficient.

In one embodiment, the energy induced by EM energy is captured by anenergy harvesting module. Energy harvesting is the process of capturingand accumulating energy from an energy source as energy from it becomesavailable; storing that energy for a period of time, and processing theenergy as appropriate so that it is in a form that can be used later,for instance to operate a microprocessor within the latter's operatinglimits. Since typically the signal voltage being carried on a materialmedium is too low to be suitable for directly powering the sensor setupby means of induction, the energy harvesting module may use acapacitor-like slow-charging electrical storage device to graduallyaccumulate the needed energy.

Since the needed power is gathered gradually, a sensor setup powered byan energy harvesting module—in one embodiment—will operate over limitedtime cycles. Once the electrical storage device is charged beyond apreset operation capacity, it begins to discharge. This dischargeeffectively turns on the sensor setup, which begins a task cycle. Thebasic requirement for a system powered by energy harvesting is that theelectrical storage device is not drained within the active period ofeach task cycle, and is sufficiently charged again during an inactiveperiod in order to power another task cycle.

Using energy induced energy to power a sensor setup gives a great degreeof flexibility in monitoring a material medium. This method of poweringis ideal for sensor setups placed at locations along a material mediumwhich are not DMARC points. Such a powering scheme also avoids a need tosetup a secondary power line to power sensor setups. In one embodiment,a majority of sensor setups could be powered by capturing induced energyflow. This embodiment gives flexibility to provide specific informationpertinent to small stretches of material medium; even when DMARC pointsare far from each other, accessing the material medium is not a viableoption, and no secondary power line is available.

The sensor setups that are powered by means of energy induced by EMenergy, in one embodiment, are reserved for: (1) less involvedfunctions, and (2) functions that are acceptably performed in pulses.Some examples of acceptable functions include making a diagnostic sensormeasurement and transmitting the measurement data using an RF signal.

In one embodiment, when a sensor setup operates in cycles, they have atask cycle that is divided into two phases, a sensing phase followed bya communication phase. The full length of a task cycle is determined bythe electrical storage device's capacity. When choosing a capacitor-likeslow-charging electrical storage device to power the sensor setup, it isselected such that there is enough time to complete a full communicationhandshake—i.e. to transmit an RF signal with the diagnostic sensor data.The length of the diagnostic sensing phase is the difference between thelength of the task cycle and the length of the communication phase. Italso needs to be recognized that there is a charging period in additionto the task cycle. The charging period is the amount of time required tocollect enough induced energy to power one task cycle.

To summarize the previously mentioned powering options, providingprimary power to a sensor setup by means of energy induced by EM energyflow along a material medium or conduit surround the material medium isideal because it avoids a need to: (1) intrude into the material mediumbeing monitored, (2) set up an independent network of material medium topower the sensor setup, or (3) use an exhaustible power supply such as aregular battery. However, due to the cyclical nature associated with theslow capturing of energy, more complicated device functions that requirecontinual powering may be reserved for other types of powering options.

FIG. 4 is a schematic representation of alternative powering optionsaccording to an aspect of the current invention. This figure illustratescapturing induced EM energy by means of an energy harvesting module asthe primary power supply for the sensor setup. A sensor setup comprisinga diagnostic sensor, 405, and an RF communication means, 407, are linkedto an energy harvesting module, 406. This module captures energy inducedby EM energy flow along a material medium, 403, or a conduit surroundingthe material medium, 404, with a capacitor-like slow-charging electricalstorage device until the device reaches a preset operating capacity, atwhich point it begins to discharge. As a backup, a secondary battery,408, is utilized. One advantage to having a backup power supply for thesensor setup is that even if the material medium has a fault—thuseliminating energy induced by EM energy flow—the sensor setup can stillmake its measurement and transmit the measurement data. Suchmeasurements from the sensor setup may be instrumental in quicklypinpointing the location and cause of the fault in the material medium.

The sensor setup as a whole is shown as 402. It is located on a materialmedium. The RF communication range is represented by 401, which showshow far the RF signal may be transmitted by the RF communication means.The RF communication means, as in FIG. 3, may be a part of thediagnostic sensor, physically attached to the diagnostic sensor as aseparate device, or just communicatively connected to the diagnosticsensor.

FIG. 5 further illustrates some powering options for a material medium,specifically an optical fiber. What has been referred to as a “fiber”,501, is actually comprised of many individual fibers. In one embodiment,most fibers, 503, are reserved for communication purposes, thuspreserving the integrity of the fiber's bandwidth. However, one or morefibers, 502, is reserved for transmitting higher levels of EM energythan are being transmitted in the other fibers. This method capturesinduced energy from leakages associated with loss phenomena of opticalsignals along a fiber. The one or more fibers transmitting higher levelsof EM energy is illustrated further in the second picture in the figure.A powering laser, 504, emits EM energy into the fiber, 502. A sensorsetup, 506, may be placed at a DMARC point where it can intrude into thefiber to receive the EM energy to power itself. Alternatively, at 505, asensor setup can be placed in proximately to the fiber and captureenergy induced by the EM energy flow through the leakages associatedwith an optical fiber's loss phenomena. The setup scenario in 505greatly expands the number of sensor setups that can be placed along thefiber, since its location is independent of needing a DMARC point.

FIG. 6 is a schematic representation of an interconnection betweenseparate devices, one for monitoring and the other for transmittingdata. A diagnostic sensor, 603, is used for monitoring a materialmedium, 604. An RF signal transmission device, 605, is used to transmitdiagnostic sensor data. In one embodiment, the two devices areelectronically and communicatively linked to one another. In anotherembodiment, the two devices are just communicatively linked to oneanother. In the figure, the dashed-lined rectangular, 602, around thetwo devices is meant to represent either of these two embodiments. Theequipment inside these dotted lines is referred to as the “sensorsetup”. The RF communication range is represented by 601. Each of thedevices is electronically connected—either directly or indirectly—to apower supply, 606. In one embodiment, one power supply is used to powerboth devices. In another embodiment, each device has its own powersupply.

RF signal transmissions can be collected in different ways. When amonitoring scheme involves only one setup, receipt of an RF transmissionis relatively straight-forward. However, when a monitoring schemeinvolves placing multiple sensor setups throughout a material medium,collection of all of the diagnostic sensor data becomes morecomplicated. Two scenarios for collecting the diagnostic sensor data aredescribed herein. For the purposes of clarity, one such scenario iscalled a Harvesting Scenario while the other scenario is called a MeshNetwork Scenario. Different types of RF signal transmission devices maybe utilized in the different scenarios, as will now be described.

In the Harvesting Scenario, the demands on each RF transmission deviceare relatively minimal. Therefore, it is sufficient to power each RFtransmission device cyclically. Powering a setup cyclically is usuallyreserved for simple functions such as diagnostic sensing and RF signaltransmission. For the Harvesting Scenario, these simple functions aresufficient.

The Harvesting Scenario is effective at detecting when the materialmedium network is up and running as well as the quality of the EM energytransmission. In one embodiment, a testing signal generator installed ata material medium's head periodically generates testing tones. The tonesmay be sent continuously or periodically in short bursts. In the lattercase, the frequency of these test tone transmissions depends on theminimum length of the sensing phase of the sensor setup. The sensingphase measures the qualities of the testing tones sent by thisgenerator. At least one testing tone burst should be generated duringthe sensing phase.

During the sensing phase, the diagnostic sensor will measure the qualityof the testing tones it receives. Post processing such as averaging maybe applied to raw measurements. The detected quality data is recordedinto data storage along with a timestamp of when the measurement istaken, which completes the sensing phase. In one embodiment, the datastorage is in the RF transmission device. The data storage may keep anumber of most recent measurement records.

In an alternative embodiment, the RF transmission device in a sensorsetup may also be connected to other diagnostic sensors such as sensorsfor measuring environmental conditions such as temperature, humidity,etc. In one embodiment, the readings of these diagnostic sensors wouldalso be entered into the data storage of the RF transmission device.

After the communication phase begins, the sensor setup will attempt tolocate a second device adapted to transmit an RF signal and establish aconnection to it. If such a connection is established, afterauthentication and other precursor operations, the diagnostic sensordata being stored on the RF transmission device can be wirelesslytransmitted along with any additional measurement data in its storageand the device's own identity, to a second RF transmission device. Whenthis transmission is completed, the communication phase ends and thesensor setup shuts down. Even if the connection is not successful, thecommunication phase completes and the sensor setup shuts off. The setupthen goes into its passive charging mode where induced power isgradually collected until enough power has accumulated to power anothercycle.

In one embodiment, the diagnostic sensor data is collected by a secondRF transmission device, for example, an operator's roaming unit. To getthe diagnostic sensor readings, the operator with the second RFtransmission device—the RF transmission device adapted to receive RFsignals—travels in order to be within the RF communication range of eachsensor setup. The operator then waits until the sensor setup completes acommunication phase of a cycle whereby the roaming unit receives thesensor setup's data concerning the material medium. This data can becollected into analysis software which intelligently determines thetrouble locations.

FIG. 7 is a schematic representation of a data harvesting scenario inwhich data is collected with a roaming unit. A testing tone generator,706, issues test tone of varying frequencies along a material medium,704. The three diagnostic sensors, 705, in the network detect the tonesand record data regarding the tones they receive. These sensor setupsalso have RF transmission means. An RF signal is transmitted and aroaming unit, 702, goes along a collection trajectory, 701. Thetrajectory is chosen such that the roaming unit goes within an RFcommunication range, 703, of each sensor setup.

A few of the strengths of the Harvesting Scenario over the exemplarymodel shown in FIG. 1 are as follows. First, in the Harvesting Scenario,a sensor setup can receive power and transmit its collected diagnosticdata without needing to intrude into a material medium. Second, giventhat a sensor setup does not need to intrude into the material medium tomake its diagnostic reading, a multiplicity of sensor setups may beplaced along the material medium with relatively minimal effort. Thesesensors can determine if EM energy is flowing through a material mediumby detecting induced energy. If the sensor detects induced energy, thenthere is EM energy flowing through the material medium. If the sensordoes not detect induced energy, then there is no EM energy flowingthrough the material medium. In the background art, data can bedetermined only at points of intrusion into the material medium. For thesake of practicality, such an evaluation is reserved for DMARC pointswhere a material medium can be more easily accessed. However, due to theinfrequency of DMARC points; to actually pinpoint a fault requiresintrusion into the material medium when troubleshooting a fault. This isan often lengthy and involved process which leads to significantinvestment of labor, expense, and loss of utility service for customers.

An alternative embodiment involves using a Mesh Networking Scenarioinstead of a Harvesting Scenario. A Mesh Network combines usage of RFsignal transmission devices that operate continuously with RF signaltransmission devices that operate in pulses. The RF devices operatingcontinuously may be described as Full Function Devices (FFD), while theRF devices operating in pulses may be described as Reduced FunctionDevices (RFD). The FFDs are primarily used in this scenario as routersand aggregators for RF signals.

In one embodiment, an RFD selects an FFD to be its “parent node”. Oneramification of establishing a parent node is that the RFD can send itsdiagnostic sensor data via RF signal to the FFD parent node. The FFDthen aggregates the data in preparation for future processing. In oneexample, an RFD determines which FFD to be its parent node based onwhich FFD within RF communication range is sending the RFD the strongestRF signals. In another example, an RFD chooses the FFD which is closestto itself to be its parent node. In the Mesh Scenario, the task cyclesof the RFDs are not only constrained by their own power charging cycle,they are also regulated by the communication cycles that are coordinatedby the RFDs' corresponding parent FFDs.

FIG. 8 is a flowchart for a Mesh Network embodiment of the invention.The process starts at step 801. If the powering is through a power lineor regular battery, the process can start at any time. If the poweringis accomplished by capturing energy induced by EM energy flow, theprocess can start when there is enough charge in the capacitor-likeslow-charging electrical storage device to power a full cycle. Step 802shows that a material medium is being monitored with a diagnosticsensor. At step 803, diagnostic sensor data is transmitted from onedevice to another device using a wireless EM signal. In one embodiment,the wireless EM signal is an RF signal.

At the next step, 804, it is determined how sensor data is retrievedfrom the Mesh Network. One deployment strategy, at step 805, ensuresthat at least one of the FFDs in the network can transmit data by RFabove ground. Through the above ground RF transmission, a roaming unitcan be placed in proximity to that FFD and gain access to the entireMesh Network. An alternative deployment strategy, at step 806, ensuresthat at least one of the FFDs has a back haul communication link.Through this back haul communication link, all sensor measurements canbe reported to a central server which, in one embodiment, automaticallyanalyzes the data. In one embodiment, the Internet is used as a backhaul network by which to transfer data to the server.

The process ends at step 807 when the transmission of the data iscompleted.

FIG. 9 is a schematic representation of a mesh network comprisingdiagnostic sensors, 902, and RF data transmission devices, 903, locatedalong a material medium, 905. Each diagnostic sensor is either onlycommunicatively coupled or both communicatively and electronicallycoupled to an RF data transmission device to make up a sensor setup,904. The Mesh Network is dependent on each of the sensor setups beingwithin RF communication range, 901, of each other. In this embodiment,each sensor setup communicates with its neighbor by propagating wirelessRF signals through the atmosphere.

FIG. 10 is a schematic representation of communication with a waveguidein a mesh network. The material medium, 1003, is surrounded by conduit,1002, which functions as a waveguide. Propagating the wireless RF signalthrough a waveguide—herein called the Waveguide Mode—has the advantageof expanding a sensor setup's RF transmission range, 1001. Propagatingthe RF signal through a waveguide allows sensor setups, 1004, to becommunicatively linked even when the sensor setups are underground andcannot successfully propagate the RF signal through the atmosphere toeach other. Additionally, the Waveguide Mode allows the sensor setups tobe placed further from each other while remaining within each other's RFcommunication range. For the purposes of this invention, transmitting awireless EM signal—such as an RF signal—over a waveguide is considered awireless transmission. A wired transmission is when non-wireless EMsignal is transmitted by a material medium.

FIG. 11 is a schematic representation of communication by couplingantennas to a material medium, 1105, in a mesh network. In thisembodiment, an electromagnetic (EM) communication device, 1102, iseither communicatively linked or electronically and communicativelylinked to a diagnostic sensor device, 1101, to make a sensor setup. In adifferent embodiment, one device performs both of these functions. Anantenna coupler, 1107, is used to attach an antenna of the EMtransmission device to the material medium. The EM transmission device'santenna is normally used to propagate an RF signal into the atmosphereor into a waveguide. Here, however, instead of transmitting RF signal,the EM transmission device transmits EM energy directly into a materialmedium by means of the direct coupler. Using the direct coupler totransmit EM energy by means of the material medium is herein called theCoupled Mode.

When using the Coupled Mode, in one embodiment, the transmitted EMenergy goes from a transmission device to a high pass filter beforeentering a material medium. The high pass filter is useful for keepingthe EM energy carrying the diagnostic sensor data separate from theother EM energy being propagated on the material medium.

The Coupled Mode has some advantages. One advantage is that it can beused even when a material medium is underground. Additionally, theCoupled Mode can be used even when the material medium or the materialmedium conduit cannot be used as a waveguide. Another advantage is thatusing the Coupled Mode expands the range over which the communicationdevices can communication, since EM energy can be propagated in thematerial medium further than an RF signal can be propagated in theatmosphere.

A power supply, 1106, powers both the sensor and the communicationdevice. In one embodiment, there is just one power source for both. Inanother embodiment, there are at least two power sources for the sensorsetup.

FIG. 12 is a schematic representation of an embodiment which combinesdifferent aspects of the invention. Additionally, in this embodiment, aspecific type of RF communication device called a Zigbee is utilized. AZigbee is a type of RF communication device that can be used tofacilitate an interconnected Mesh Network, as will be shown in detail inFIGS. 13-15. An advantage of the Zigbee device is that it is InternetProtocol (IP) enabled and addressable. Being IP enabled and addressablemeans that each Zigbee device has a unique way to be identified, whichhelps to facilitate making an integrated network among several differentZigbee devices. Also, a Zigbee network administrator can probe fordiagnostic sensor data concerning a specific location by calling the IPaddress of the Zigbee device in that specific location. This ability topinpoint diagnostic sensor data is helpful in troubleshooting a fault ina material medium.

Zigbee is just one of several device types than is able to self-organizeinto a store-and-forward multi-hop wireless mesh network with at leastone other device capable of transmitting RF signal. Some of the otherexamples of similar device types are: Wibree devices, EnOcean devices,and SNAP devices.

The concept of the Mesh Network being able to “self-organize” which wasmentioned above means that devices are installed with algorithm andprotocol implementations that, when run, can figure out how to forwarddata from an arbitrary source to an arbitrary destination within thenetwork according to certain predetermined policies. These devices canalso compute any logical network structure that needs to be built, (i.e.figure out a hierarchy relationship among nodes if the forwardingalgorithm requires such), for completing data forwarding computation,and other related tasks as well. See FIG. 15 for an illustration of sucha hierarchy relationship.

By devices exchanging and propagating information regarding with whomeach device throughout the network can communicate, a topology graph canbe constructed and each device can use this graph to compute theshortest path towards any destination. Then when a device receives datathat requires forwarding—that is, this device is not the finaldestination for the data—it knows to which device it should forward thisdata.

In this embodiment, a diagnostic sensor, 1205, is communicativelyconnected to the Zigbee device, 1204, to make a sensor setup. The sensorsetup has at least three options for how to communicate with aneighboring sensor setup. The sensor setup can propagate wireless EMsignals, such as RF signals, into the atmosphere and into a materialmedium conduit, 1203, or the sensor setup can propagate EM signalsdirectly into a material medium, 1202, by means of a direct coupler,1207. When direct couplers are used to communicate, then the sensorsetups would be linked into a material medium, not merely placedsurrounding a material medium as is depicted in the figure.

The sensor setup is powered, in this embodiment, by an energy-harvestingmodule, 1206, for its primary power source. The power collected by theenergy-harvesting module may be stored in a capacitor-like slow-chargingelectrical storage device. As a secondary power source, a regularbattery, 1208, is employed.

FIG. 13 is a schematic representation of a mesh network deployment wheredata is collected with a roaming unit, 1307. The Mesh Network is made upof Full Functional Devices (FFD), 1303, and Reduced Function Devices(RFD), 1301. The FFDs require constant power in order to do more complexoperations such as serving as routers for RFDs and mesh networkcoordinators. A straightforward way to supply the constant powering isto put the FFDs at DMARC points in the system. An example of a DMARCpoint, 1302, is where two material media meet. At the DMARC points, theFFD can readily access the material medium. Therefore, energy can betransmitted along the material medium to power the FFD. The RFDs mayoperate in pulses. This allows for powering an RFD by use of energyinduced by EM energy flow through a material medium or the materialmedium's conduit, and to capture this energy with a capacitor-likeslow-charging electrical storage device. In this embodiment, each RFDfinds the closest parent FFD within the RFD's radio frequency (RF)communication range, 1305, and transmits its identity and diagnosticsensor data to the FFD.

The FFDs then communicate with other FFDs within each others RFcommunication range, 1304. The FFDs may communicate with each other bytransmitting the RF signal through the atmosphere, by transmitting theRF signal into a material medium waveguide, or by transmitting the RFsignal directly into a material medium by means of a direct coupler.

This embodiment utilizes a roaming unit, 1307, equipped to receive RFsignal transmitted into the atmosphere. Therefore, at least one of theFFDs needs to transmit an RF signal into the atmosphere. This is done onFFD number 1 by means of an antenna, 1306. However, FFD number 1 is notlimited to communicating with the other FFDs in the network by means ofpropagating RF signal into the atmosphere. Rather, it can use any meansof RF communication previously discussed, or any other means known inthe art. The roaming unit takes a path 1308 so that the unit passeswithin the transmission range of FFD number 1.

FIG. 14 is a schematic representation of a mesh network deployment wheredata is collected with a back haul communication link, 1401. This figureis identical to the Mesh Network Scenario in FIG. 13, except instead ofusing a roaming unit to collect the network data from one of the FFDswhich propagates RF signal into the atmosphere; this embodiment collectsdata by means of a back haul communication link. An example of a backhaul communication link is a wireless IP broadband connection such as a4G WiFi Neighborhood Area Network connection. An example of a back haulnetwork is the Internet. In one embodiment, a server connected to theback haul network is used to collect and process the Mesh Network data.

The FFDs that can communicate with each other form a Mesh Network. Inthis embodiment, the deployment strategy ensures that for each MeshNetwork, there is at least one RF transmission device which has a backhaul communication link. Through this back haul communication link, allsensor measurements can be reported to a central server whichautomatically analyzes the data.

For the Mesh Network Scenarios previously described, it may not benecessary to have a testing tones generator, see 706, and diagnosticsensor setups designated to measure the testing tones. In the embodimentwhere the RF signals are propagated in a waveguide—either the materialmedium itself or a conduit surrounding the material medium—the abilityof one sensor setup to communicate with another sensor setup implies theconnectivity of the underlying material medium system between these twosetups. Therefore, detecting the connectivity of the entire Mesh Networkconfirms the connectivity of the underlying material medium system. Totake advantage of this information, the topology of the mesh networksformed among sensor setups will need to be reported to a central server.This can be done when each sensor setup reports the identities of itsmesh neighbors.

While connectivity of a Mesh Network may avoid a need to have specificsensors for detecting testing tones issued by a testing tone generator;it is still desirable to measure local environmental conditions inproximity to the material medium. Therefore, having diagnostic sensorscoupled to RF communication means or devices is desirable, even in aninterconnected Mesh Network.

FIG. 15 is a schematic representation of a mesh network topology of FIG.14 as a hierarchy relationship. The Mesh Network is made up of FFDs andRFDs. In this embodiment of the Mesh Network, each RFD identifies an FFDas its parent node. In the Mesh Network from FIG. 14, RFDs numbers 4 and6 make FFD number 5 their parent node. RFD number 3 make FFD number 2its parent node. Furthermore, FFDs numbers 1, 2 and 5 areinterconnected—since they are within at least one of the other FFD's RFtransmission range.

This hierarchy relationship shows FFD number 1 possessing both anantenna, 1501, and a back haul communication link, 1502. This is onlyfor illustration purposes, since one of these connection types issufficient to communicate data outside of the Mesh Network.

For example, in FIG. 13, in 1306, FFD number 1 possessed an antenna fortransmitting RF signal into the atmosphere, thus allowing a roamingunit, 1307 to travel on a path, 1308, such that the roaming unit wouldbe within RF transmission range of the FFD device. This allows theroaming unit to recover all Mesh Network diagnostic sensor measurements.

Alternatively, in FIG. 14, FFD number 1 possesses a back haulcommunication link, 1401, which allows all Mesh Network diagnosticsensor measurements to be transmitted to a server by means of a backhaul network.

FIG. 16 shows monitoring a series of diagnostic sensors located on anabove and below ground material medium. Sensor setups, 1601, are locatedin various positions along a material medium, 1602. Sensor setup number1 is located above ground, while sensor setups number 2 and 3 arelocated below ground. This figure shows the versatility of the sensorsetups, allowing for diagnostic monitoring is various differentlocations along a material medium.

FIG. 17 shows monitoring a material medium as it goes to an end devicein a facility, building or residence. In this embodiment of theinvention, diagnostic monitoring extends past a DMARC point locatedoutside of the facility, building or residence. This embodimentessentially expands a “network edge” DMARC point from outside a user'slocation to including the material medium inside a user's location allthe way to a user's device. Some examples of a utility being deliveredto a user include telecommunication's service and power service.

The figure shows several sensor setups, 1704, that are numbered 1, 2,and 3. In this embodiment, the sensor setups are used to monitor amaterial medium, 1701, from a DMARC point, 1702, as the material mediumenters a facility, building, or residence, 1703, and proceeds to auser's end device, 1705. In this embodiment, the material medium iscarrying telecommunication's service to a user's telecommunicationdevice. Other embodiments with other user devices and other utilityservices may be envisioned.

Sensor setup number 1 allows for sensing the utility service at a DMARCpoint as a service material medium departs from a main material medium.Sensor setup number 2 allows for sensing the utility service at anintermediate point inside a facility, building, or residence. Sensorsetup number 3 allows for sensing the utility service at the user's enddevice. Alternatively, the sensor setups may be used to detect anenvironmental condition at these various locations.

FIG. 18 shows some possible diagnostic sensor measurements of interestwhen monitoring a material medium. One type of measurement is EM energyflow, which measures the material medium's operability. Another type ofmeasurement is an environmental condition, which measures anenvironmental condition in proximity to a material medium instead of theoperability of the material medium itself. An environmental measurementallow for detecting potential threats to a material medium's operationalhealth. Additionally, an environmental measurement may be used toidentify a potentially threatening environmental condition to astructure in proximity to the material medium. Some environmentalconditions of interest include: temperature, pressure, moisture,vibrations, presence of a chemical, and wind speed. Other environmentalconditions of interest may also be envisioned.

FIG. 19 shows how a material medium can be used to monitor environmentalconditions in a tunnel. In this embodiment, a tunnel, 1901, has had aninflux of water, 1902, which is flooding the lower part of the tunnel.By using sensor setups, 1904, equipped with diagnostic sensor forsensing a presence of moisture in proximity to a material medium, 1903,this flooding problem can be detected early. An early detection of themoisture problem allows for earlier troubleshooting to be done. Anadditional advantage is that if there is a threat to the tunnel'sstructural integrity, potential victims can be timely evacuated from thelocation before a catastrophic failure.

FIG. 20 shows how a material medium can be used to monitor environmentalconditions on a bridge. In this embodiment, a storm condition, 2001,travels past a bridge, 2002. Sensor setups, 2003, are placed along amaterial medium, 2004. Some conditions of interest concerning a bridgeinclude detecting wind speed and vibrations. If these conditions exceeda normal range, then early action can be taken to avoid harm to thoseusing the bridge. Additionally, it may be possible to take precautionsin maintaining the integrity of the bridge's structure. The foregoingDetailed Description is to be understood as being in every respectillustrative and exemplary, but not restrictive, and the scope of theinvention disclosed herein is not to be determined from the DetailedDescription, but rather from the claims as interpreted according to thefull breadth permitted by the patent laws. It is to be understood thatthe embodiments shown and described herein are only illustrative of theprinciples of the present invention and that various modifications maybe implemented by those skilled in the art without departing from thescope and spirit of the invention. Those skilled in the art couldimplement various other feature combinations without departing from thescope and spirit of the invention.

1-22. (canceled)
 23. A method comprising: monitoring the operationalstatus of a material medium; generating first data corresponding to theoperational status of the material medium, based on the monitoring;receiving second data originating from a remote sensor, the second datacorresponding to the operational status of the material medium and basedon the remote sensor monitoring the material medium; detecting a roamingunit; and transmitting the first and second data to the roaming unit.24. The method of claim 23, further comprising powering the remotesensor using energy induced by electromagnetic energy transmitted by thematerial medium.
 25. The method of claim 23, further comprising poweringthe remote sensor using energy induced by electromagnetic energytransmitted by a conduit adjacent to the material medium.
 26. The methodof claim 23, where the remote sensor is a reduced function device. 27.The method of claim 23, where the second data is received via awaveguide.
 28. The method of claim 27, where the waveguide is thematerial medium.
 29. The method of claim 27, where the waveguide is aconduit adjacent to the material medium.
 30. The method of claim 23,where the second data comprises an IP address of the remote sensor. 31.The method of claim 23, further comprising issuing a test tone along thematerial medium.
 32. The method of claim 23, where the material mediumcomprises a body of water.
 33. A system comprising: a first sensorconfigured to monitor the operational status of a material medium and togenerate first data based on the monitoring by the first sensor; asecond sensor configured to: monitor the operational status of thematerial medium; generate second data based on the monitoring by thesecond sensor; receive the first data; transmit the first data and thesecond data; and a roaming unit configured to receive the first data andthe second data.
 34. The system of claim 33, wherein the first sensor isfurther configured to generate power using energy induced byelectromagnetic energy transmitted by the material medium.
 35. Thesystem of claim 33, wherein the first sensor is further configured togenerate power using energy induced by electromagnetic energytransmitted by a conduit adjacent to the material medium.
 36. The systemof claim 33, where the first sensor is a reduced function device. 37.The system of claim 33, where the second sensor is configured to receivethe first data via a waveguide.
 38. The system of claim 37, where thewaveguide is the material medium.
 39. The system of claim 37, where thewaveguide is a conduit adjacent to the material medium.
 40. The systemof claim 33, where the first data comprises an IP address of the firstsensor.
 41. The system of claim 33, further comprising a test tonegenerator configured to issue a test tone along the material medium. 42.The system of claim 33, where the material medium comprises a body ofwater.